:root {
    --bg:          #0b0d10;
    --bg-elev:     #0f1216;
    --rule:        #1c2026;
    --rule-strong: #2a2f37;
    --text:        #e6e8eb;
    --text-body:   #c8ccd1;
    --text-dim:    #8b9098;
    --text-faint:  #5a6068;
    --link:        #9ab6ff;
  }

  *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  html { scroll-behavior: smooth; }

  ::selection { background: var(--rule-strong); color: var(--text); }
  ::-webkit-scrollbar { width: 6px; }
  ::-webkit-scrollbar-track { background: var(--bg); }
  ::-webkit-scrollbar-thumb { background: var(--rule-strong); }

  body {
    background: var(--bg);
    color: var(--text-body);
    font-family: 'IBM Plex Sans', system-ui, sans-serif;
    font-size: 14px;
    line-height: 1.75;
    padding: 36px 36px 100px;
    max-width: 900px;
    margin: 0 auto;
    -webkit-font-smoothing: antialiased;
  }

  /* ─── TOP NAV ────────────────────────────────────────────── */
  .topnav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 52px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--rule);
  }

  .topnav-link {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--text-faint);
    text-decoration: none;
    transition: color 0.12s;
  }

  .topnav-link:hover { color: var(--link); }

  .topnav-right { display: flex; gap: 20px; }

  /* ─── HEADER ────────────────────────────────────────────── */
  .header {
    border-bottom: 1px solid var(--rule);
    padding-bottom: 24px;
    margin-bottom: 36px;
  }

  .header .meta {
    font-family: 'IBM Plex Mono', monospace;
    color: var(--text-faint);
    font-size: 10.5px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    margin-bottom: 18px;
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
  }

  .header h1 {
    font-family: 'IBM Plex Serif', serif;
    font-size: clamp(40px, 5.8vw, 58px);
    font-weight: 400;
    line-height: 1.1;
    letter-spacing: -0.01em;
    color: var(--text);
    margin-bottom: 14px;
  }

  .header h1 em { font-style: italic; color: var(--text); font-weight: 400; }

  .header .subtitle {
    color: var(--text-dim);
    font-size: 13.5px;
    max-width: 580px;
    line-height: 1.75;
  }

  /* ─── CONTROLS ──────────────────────────────────────────── */
  .controls { margin-bottom: 28px; display: flex; flex-direction: column; gap: 14px; }

  .search-wrap { position: relative; }

  #search {
    width: 100%;
    background: var(--bg-elev);
    border: 1px solid var(--rule-strong);
    border-radius: 3px;
    color: var(--text);
    font-family: 'IBM Plex Sans', system-ui, sans-serif;
    font-size: 13.5px;
    padding: 10px 90px 10px 14px;
    outline: none;
    appearance: none;
    transition: border-color 0.15s, box-shadow 0.15s;
  }

  #search::placeholder { color: var(--text-faint); }

  #search:focus {
    border-color: var(--link);
    box-shadow: 0 0 0 3px rgba(154, 182, 255, 0.08);
  }

  .search-kbd {
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    font-family: 'IBM Plex Mono', monospace;
    color: var(--text-faint);
    font-size: 9.5px;
    letter-spacing: 0.08em;
    pointer-events: none;
    user-select: none;
  }

  .filter-row {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
  }

  .chips { display: flex; gap: 6px; flex-wrap: wrap; flex: 1; }

  .chip {
    background: transparent;
    border: 1px solid var(--rule-strong);
    border-radius: 2px;
    color: var(--text-faint);
    font-family: 'IBM Plex Mono', monospace;
    font-size: 9.5px;
    letter-spacing: 0.13em;
    text-transform: uppercase;
    padding: 5px 10px;
    cursor: pointer;
    transition: border-color 0.15s, color 0.15s, background 0.15s;
    white-space: nowrap;
    display: inline-flex;
    align-items: center;
    gap: 5px;
  }

  .chip:hover { border-color: var(--rule-strong); color: var(--text-dim); }

  .chip.active {
    border-color: var(--link);
    color: var(--link);
    background: rgba(154, 182, 255, 0.06);
  }

  .chip-n { opacity: 0.55; font-size: 8.5px; }

  .result-info {
    font-family: 'IBM Plex Mono', monospace;
    color: var(--text-faint);
    font-size: 9.5px;
    letter-spacing: 0.13em;
    text-transform: uppercase;
    white-space: nowrap;
  }

  #result-count { color: var(--text-dim); }

  /* ─── GRID ──────────────────────────────────────────────── */
  .tutorial-grid {
    display: grid;
    gap: 14px;
    grid-template-columns: 1fr;
  }

  @media (min-width: 660px) {
    .tutorial-grid { grid-template-columns: 1fr 1fr; }
  }

  /* ─── CARD ──────────────────────────────────────────────── */
  .tutorial-card {
    border: 1px solid var(--rule-strong);
    background: var(--bg-elev);
    border-radius: 3px;
    padding: 22px 24px 20px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    text-decoration: none;
    color: inherit;
    position: relative;
    overflow: hidden;
    transition: border-color 0.14s;
    cursor: default;
  }

  .tutorial-card::before {
    content: '';
    position: absolute;
    left: 0; top: 0; bottom: 0;
    width: 2px;
    background: var(--rule-strong);
    transition: background 0.14s;
  }

  /* Only linked (a-tag) cards get full hover */
  a.tutorial-card { cursor: pointer; }

  a.tutorial-card:hover { border-color: var(--link); }
  a.tutorial-card:hover::before { background: var(--link); }
  a.tutorial-card:hover h2 { color: var(--link); }

  /* card head row */
  .card-head {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 2px;
  }

  .card-num {
    font-family: 'IBM Plex Mono', monospace;
    color: var(--text-faint);
    font-size: 10px;
    letter-spacing: 0.18em;
    font-weight: 500;
  }

  .cat-badge {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 8.5px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    padding: 2px 7px;
    border-radius: 2px;
    color: var(--text-dim);
    border: 1px solid var(--rule-strong);
    background: transparent;
  }

  .new-badge {
    margin-left: auto;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 8px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    padding: 2px 6px;
    border-radius: 2px;
    color: var(--link);
    border: 1px solid rgba(154, 182, 255, 0.30);
    background: rgba(154, 182, 255, 0.06);
  }

  .tutorial-card h2 {
    font-family: 'IBM Plex Serif', serif;
    font-size: 20px;
    font-weight: 400;
    color: var(--text);
    letter-spacing: -0.01em;
    line-height: 1.2;
    margin-top: 2px;
    transition: color 0.14s;
  }

  .card-desc {
    color: var(--text-dim);
    font-size: 13px;
    line-height: 1.7;
    flex: 1;
    margin: 2px 0 4px;
  }

  .subguides {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
    margin: 2px 0 4px;
  }

  .sg {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 9px;
    letter-spacing: 0.05em;
    padding: 2px 7px;
    border-radius: 2px;
    background: transparent;
    color: var(--text-faint);
    border: 1px solid var(--rule);
  }

  .card-meta {
    font-family: 'IBM Plex Mono', monospace;
    color: var(--text-faint);
    font-size: 10px;
    letter-spacing: 0.06em;
    border-top: 1px solid var(--rule);
    padding-top: 11px;
    margin-top: 2px;
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
  }

  .meta-item::before { content: "· "; color: var(--text-faint); }

  .card-cta {
    font-family: 'IBM Plex Mono', monospace;
    color: var(--text-dim);
    font-size: 10.5px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    margin-top: 4px;
    display: inline-flex;
    align-items: center;
    gap: 5px;
    transition: color 0.14s;
  }

  .card-cta::after { content: "→"; transition: transform 0.12s; }
  a.tutorial-card:hover .card-cta { color: var(--link); }
  a.tutorial-card:hover .card-cta::after { transform: translateX(4px); }

  .card-cta.dim {
    color: var(--text-faint);
    cursor: default;
  }

  .card-cta.dim::after { content: ""; }

  /* ─── SOON CARD ─────────────────────────────────────────── */
  .soon-card {
    border: 1px dashed var(--rule);
    border-radius: 3px;
    padding: 26px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 12px;
    min-height: 180px;
  }

  .soon-label {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 9px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--text-faint);
    font-weight: 500;
  }

  .soon-card > p { color: var(--text-faint); font-size: 12px; line-height: 1.6; }

  .soon-tags { display: flex; flex-wrap: wrap; gap: 6px; }

  .soon-tag {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 9px;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    padding: 2px 8px;
    border-radius: 2px;
    border: 1px solid var(--rule);
    color: var(--text-faint);
  }

  /* ─── EMPTY STATE ───────────────────────────────────────── */
  .empty-state {
    display: none;
    padding: 64px 24px;
    text-align: center;
    color: var(--text-faint);
  }

  .empty-glyph { font-size: 28px; margin-bottom: 16px; opacity: 0.25; }
  .empty-state p { font-size: 13px; margin-bottom: 20px; }

  .empty-btn {
    background: transparent;
    border: 1px solid var(--rule-strong);
    color: var(--text-dim);
    font-family: 'IBM Plex Mono', monospace;
    font-size: 10px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    padding: 8px 18px;
    border-radius: 2px;
    cursor: pointer;
    transition: border-color 0.15s, color 0.15s;
  }

  .empty-btn:hover { border-color: var(--link); color: var(--link); }

  /* ─── STATS ─────────────────────────────────────────────── */
  .stats {
    display: flex;
    gap: 0;
    margin-top: 52px;
    padding-top: 28px;
    border-top: 1px solid var(--rule);
    flex-wrap: wrap;
  }

  .stat { display: flex; flex-direction: column; gap: 5px; padding-right: 44px; }

  .stat-value {
    font-family: 'IBM Plex Serif', serif;
    font-size: 32px;
    font-weight: 400;
    color: var(--text);
    letter-spacing: -0.02em;
    line-height: 1;
  }

  .stat-label {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 9px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--text-faint);
  }

  /* ─── FOOTER ────────────────────────────────────────────── */
  footer {
    margin-top: 72px;
    padding-top: 24px;
    border-top: 1px solid var(--rule-strong);
    color: var(--text-faint);
    font-family: 'IBM Plex Mono', monospace;
    font-size: 11px;
    text-align: center;
    letter-spacing: 0.08em;
  }

  .glyph { color: var(--text-faint); margin: 0 8px; }
  footer a { color: var(--text-faint); text-decoration: underline; text-underline-offset: 3px; }
  footer a:hover { color: var(--link); }